Chemical Science International Journal

The process of obtaining fertilising precipitate based on the interaction of off-balance ore phosphorites of Central Kyzylkum and chemically enriched phosphorite concentrate with hydrochloric acid, followed by precipitation of hydrochloric acid extraction with suspension of calcium hydroxide. The optimal parameters of the precipitation were determined for the first time in our country. Influence of calcium hydroxide norms on degree precipitation hydrochloricphosphoric acid extracts are studied. The resulting samples of precipitates under optimal conditions contain in their composition 23.63-24.19% P₂O_5(t.), 21.09-21.38% P₂O_5accep. by 2% citric acid to those 26.97-28.41% CaO_(t.), 23.52-25.59% of CaO_accep.by 2% citric acid. The degree of precipitation equal 94.01-98.05%. Physical and chemical studies (x-ray phase analysis) of the mineralised mass and products of its processing were also carried out.

Increase in domestic and industrial waste increases the concentration of trace metals in dumpsites soil. The level of trace metal concentration of dumpsite soil needs to be analysed for proper metal contamination management. Soil metal contamination can be managed using organic material such as carbonised sawdust. In this study, soil samples were collected from selected dumpsites in Benin City, using standard method.

Carbonised briquette was prepared from softwood sawdust obtained Carbonised briquette was prepared from softwood sawdust obtained from a sawmill in Sapele Town. The effects of carbonised briquette on metal fractionation were investigated using standard method. Fraction studies revealed that carbonised briquette the amendment results in the decrease in the levels of Zn, Cu, Mn and Cr in the different fractions. The decrease follows the order: exchangeable < carbonate < Fe-Mn oxide < organic < residual. Suggesting reduction in mobility and bioavailability of the metals after carbonised briquette amendment.

Therefore, this study revealed that carbonised briquette can be used to immobilise metals and also as a medium to manage trace metals soil contamination.

The inhibition capability of Triumfetta rhomboidea (TR) leaves extract on the corrosion of carbon steel in I M HCl was evaluated using weight loss technique. Scanning electron microscopy (SEM) analysis was also performed. Results showed that the extract acts as a good inhibitor for carbon steel and its efficiency increases with an increase in its concentration and exposure time. The SEM observations confirmed the existence of a protective film of inhibitor on carbon steel surface. The inhibiting action of Triumfetta rhomboidea extract was attributed to the phytochemical species present in the extract and its adsorption on the carbon steel surface. The adsorption of Triumfetta rhomboidea extract on carbon steel surface obeys Langmuir adsorption isotherm with physical adsorption on the metal surface.

Modified carbon paste electrode (CPE) by cobalt hexacyanoferrate (CoHCF) was prepared and the sensitivity of the prepared electrode was analyzed by differential pulse voltammetry. The electrochemical behavior of methylene blue on cobalt hexacyanoferrate modified carbon paste electrode (CoHCF / MCPE) has been investigated by differential pulse voltammetric technique. Also the detection limit of modified electrode was investigated on methylene blue dyes from textile industrial waste water. By the prepared electrode 1.222×10^-4 M, 1.214×10^-4 M and 1.217×10^-4 M Methylene blue was detected in the textile effluent at three sample sites and 100.5 to 104.5 % of recovery was calculated. The prepared and modified electrode was efficiently detects 1.053 x10^-6 limit of detection.

Aims: The study had for objective to estimate the effect of the stimulating ones of natural defense in the defense of plants.

Place and Duration of Study: Laboratory of Biology and Improvement of Crop Production (Nangui Abrogoua University, Abidjan, Côte d’Ivoire), between February 2018 and August 2018.

Methodology: Thus, the effect of the exogenous application of methyl jasmonate and ethephon on the accumulation of phenolic compounds in cotton [Gossypium hirsutum L. (Malvaceae)] grown in natura was tested. The efficacy of methyl jasmonate and ethephon was subsequently inoculating the cotton plants with a virulent strain of FOV.

Results: The results showed the ability of both stimulators to induce an accumulation of phenolic compounds in cotton. However, the treatment combining the two molecules (MeJA + ETH) was more effective compared to that with MeJA, followed by ETH. Qualitative analysis by HPLC showed the de novo synthesis of Gossypine, Pterosilbene and Resveratrol, which can be considered as phenolic markers of the precondition state of cotton. The exogenous application of MeJA and ETH allowed an amplification of the level of synthesis of phenolic compounds. Inoculation experiments with FOV, a causal agent for Fusarium wilt in cotton, confirmed the efficacy of methyl jasmonate and ethephon. These two molecules conferred protection of cotton plants against FOV.

Conclusion: The stimulation of cotton defense systems by the use of SDN is, therefore, an interesting alternative to chemical control. Its application in the agricultural sector could contribute to the development of a reasoned and sustainable agriculture that is, therefore, more respectful of the environment and human health.